Synchronous self-starting motor



June 1932' J. w. HANSEN ET AL SYNCHRONOUS SELF STARTING MOTOR Filed Feb. 9, 1931 8 l7 5 4//Rom/E0 @7652 3 IN VENTOR JUL/US W HANSEN WILLIAM L. HIM/SEN.

BY IRA /v. Humsr.

ATTORNEY Patented Jim 2 1932 UNITED STATES PATENT OFFICE 'mms w. HANSEN, WILLUM L. HANsEN, AND IRA N. mar, or rnINcE'roN, INDIANA,

AssIeNons 'ro nANsEN MANUFACTURING comrANY, INCL, or PRINCETON, INDIANA,

, A OOBPORATIOH INDIANA SYNCHBONOUS SELF-STARTING- MOTOR Application filed February 9, 1931. Serial No. 514,336.

Our invention relates to synchronous, selfstarting motors.

It is the object of our invention to providea synchronous, self-starting motor, particularly useful in connection with clocks.

In particular, it is our object to provide a multi-polar motor with a bridging ring of our invention to provide for a self-starting motor with a rotor whose periphery has regular inrical and geographical oles but still having the advantages of a sel -starting motor.

It is our further object to provide a motor with a very narrow air gap, thereby producing high efficiency with a motor of minimum size, and it is our object tolprovide a rotor with a periphery having toothed segments on the margin thereof for the purpose of inducing the starting of the motor.

It is our further object to providesuch a motor having fields, a portion of which lag behind the other portion.

It is our particular object to provide a synchronous, self-startin motor having a '25 hardened steel bridging ring and a soft steel rotor.

This application is in part a continuation of application Ser. No. 362,356, atented Sept. 15, 1931, No. 1,823,601, filed ay 11, 30 1929.

' Referring to the drawing:

Figure 1 is a vertical longitudinal section through the motor.

Figure 2 is a vertical transverse section as through the motor.

Referring to the drawing in detail, the motor of our invention is mounted uponthe aseg, or any other suitable support. Upon 40 each arm having an arcuate pole face divided into pole portions 6 and 7 ,the portion 7 havin a plurality of shading coils 8.

he arms 2 and 3 and the arms and are joined together by their respective bridge 46' pieces 9 around which are wrapped the field coils 10. I These coils are connected together by the wire 11, the respective ends of the wire being designated 12 and 13, suitably connected into an alternating current circuit.

Mounted upon the arcuate ends of the b1- dentations, having the advantage of geomet-' The rotor has double the use are mounted the arms 2, 3, 4 and 5,

furcated pole portions 6 and 7 is a hardened steel collector ring 14, which is preferably glass hard. This hardened steel magneticbridging ring is fundamentally one of the important featuresof our invention. Within this hardened steel ring and closely adjacent to it, separated from it by a very narrow air gap, is a soft steel rotor 15 mounted on the shaft 16, suitably supported in the supportmg plates 17 and spider 18.

This rotor is provided with a plurality of slots 19, each having a straight face 20 and an arcuate face 21 and provided with an overhanging hook 22 formed on the outwardly extending finger piece 23.

Our motor is self-starting and operates synchronously.

The rotor is made of magnetic material, of which material soft carbon steel is a good ex ample.

The purpose of the hardened steel ring 14 is to concentrate the magnetism between the field pole pieces and it also tends to collect the stray lines of magnetism between the pole pieces, thereby making. the motor more eflicient. The steel ring may be made of carpassage of magnetic lines of force. number of pole pieces that the stator has and this rotor is made of magnetizable materials. In the particular embodiment disclosed in our applica tion, we have shown' four poles in the stator and eight pole pieces in the rotor, but we do not wish to confine this invention to any particular number. The projections. 22 of the rotor cooperate with the shading coils 8 of the field pole pieces insuch a manner as 'to create a rotating field flux in the same direction in which the projections extend.

It will be understood that wedesire to comprehend within our invention such modifications as may be clearly embraced within the sage of our'claims and invention.

aving thus fully described our invention, what'we' 'claim as new and desire to secure by Letters Patent, is:

1. A synchronous self-starting motor having, in combination, a stator having means 'bon steel or other material having reluctance to the for producing a progressive magnetic field,

a hardened steel bridging ring mounted thereon, and a rotor with geometrical pole members revolving within said ring.

2. A synchronous selftarting motor hav- 5 ing, in combination, a stator having means for producing a progressive, magnetic field, a hardened steel bridging ring mounted thereon, and a rotor with geometrical pole members revolving within said ring, said rotor soft steel.

3. In a synchronous self-starting motor, a

stator, shading coils mounted thereon, a hard-.

ened steel ring mounted on said stator, and a eometricall polar rotor mounted within said ring, sai rotor havin a plurality of radially arranged PlOjGCtlOIlS with slots therebetween. 3

4. In a synchronous self-starting motor, a stator, shading coils mounted thereon, a hardened steel ring mounted on said stator, and a rotor mounted within said ring, said rotor having a plurality of radially disposed projections forming slots, and horns on said rotor plrojections extending over a portion of said s ots.

5. In a synchronous self-starting motor, a stator, shading coils mounted thereon, a hardened steel ring mounted on said stator, and 'a :0 rotor mounted within said ring, said rotor having a plurality of radially disposed projections, and horns on said rotor extending laterally from the ends of the projections,

said rotor bein of soft steel.

6. In a sync ronous self-startin motor, the combination of a stator having eld coils and pole pieces of even number, shading coils mounted on said oles, a highly retentive on the stator, and a ra within said ringhaving double the number of slots to the number of poles of the stator.

7 In a synchronous self-startin motor,

the combination of a stator having eld coils even number, shading and pole pieces of coils mounted on said poles, a highly retentive magnetic stationary rid (gang ring mounted on the stator, and a ra ially slotted rotor within said rlng other. 7

8. In a synchronous self-starting motor, a

the combination of a stator having means for .being composed of magnetic materials such as magnetic stationary ridgiiig tiipunted a v 1a y s 0 r0 or and a radially slotted rotor of soft steel revolving within said rin andrhorns on said rotor pro]ecting partia y across said slots IRA N. HURST.

om one pole towards the J producing a progressive magnetic field, a

highly retentive magnetic stationary bridging ring of hardened steel mounted on the stator, and a radially slotted rotor of soft. steel re- '0 volving within said ring. 7

- 9. In a vsynchronous self-starting motor, the combination of a stator havingmeans for producing a progressive magnetic field, a highly retentive magnetic stationary bridging O ring of hardened steel mounted on the stator, 

